They come from the factory with a turbo on each side built into the exhaust manifold, so all they need is an ecu tune + better down pipe/high flow cat/etc.
Stock it did 303hp/308tq on the dyno at the wheels
Exhaust + tune: 346hp / 320tq
Assuming a typical 15% drivetrain loss, this is around 397hp "at the crank" / 368tq
the downside is that it's a pig at 3700-4000lbs, but the tq curve is virtually flat, so it's probably very predictable approaching the limits with no surprises of boost induced oversteer mid corner.
Hopefully the new Z is lighter with the same motor on the same platform, but not $65k, more like $40k (without the mindless "adaptive" steering <--- they ran out of ideas apparently).
The Q will be a sweet car to pickup after the $30k-$40k depreciation hit in 36-48 months, and/or lease returns.
Likewise my 3.5l ecoboost F150 2011 now has 107k miles and was tuned within the first few months of owning it. Dyno'd 375rwhp and 515rwtq... kinda torquey for a 3.5 but it rides good. Pulls 13.5's in June heat. Not bad for a 5300lb truck and my fat butt.